Panel finds misconduct by bubble fusion researcher

Controversy has brewed once again over “bubble fusion”, once hailed as potential green energy source. Nuclear engineer Rusi Taleyarkhan, who claimed in 2002 to have achieved nuclear fusion by popping bubbles in a solvent, has been accused of research misconduct by Purdue University in West Lafayette, Indiana.

Taleyarkhan, who was then at Oak Ridge National Laboratory in Tennessee and is now at Purdue, claimed in the journal Science that by bombarding a cool solvent with neutrons and sound waves, his team created bubbles that triggered nuclear fusion. Such a feat could pave the way to abundant cheap and clean power.

The idea was that the imploding bubbles heated up to around 10 million °C, hot enough to start conventional nuclear fusion. Taleyarkhan detected neutrons coming out of the solvent, which he took to be a by-product of fusion.

But sceptics pointed out that the maximum likely temperature of the collapsing bubbles was something like 20,000 °C, not hot enough for fusion. Scientists suspected the neutrons Taleyarkhan saw came from another source and other teams failed to replicate his results, suggesting fusion never happened in these experiments, at least at detectable levels.

Advertisement

Two counts

In 2006, a Purdue committee began investigating allegations of misconduct against Taleyarkhan, and in early 2007, the committee cleared Taleyarkhan and his team of misconduct.

But a second investigation began in May 2007 when further, secret allegations surfaced. These allegations were made public on Friday, when Purdue announced that it had completed its second investigation, which concludes that Taleyarkhan committed two counts of misconduct.

The first is that he added the name of a researcher called Adam Butt to the list of authors of his bubble fusion papers, knowing that Butt was not a significant contributor to the experiments, data analysis or paper preparation.

“The sole apparent motivation for the addition of Mr Butt was a desire to overcome a reviewer’s criticism,” says the committee’s investigation report (pdf).

False assertion

Secondly, in a 2006 paper in Physical Review Letters, Taleyarkhan stated that the experimental results reported in his original Science paper “have now been independently confirmed”. The committee concluded that this assertion was false and constituted misconduct.

Taleyarkhan was cleared of seven further misconduct allegations, however, including plagiarism. And although the report says he allowed a press release to be “crafted in a very misleading way”, the committee decided this was not clearly part of the scientific record, being aimed at the general public, and did not constitute research misconduct.

The university has given Taleyarkhan, who could not be reached for comment for this story, 30 days to appeal against the allegations.

“Any decision on sanctions by the university based on the committee’s conclusions will come after the appeal process,” says Joseph Bennett, Purdue’s vice president for university relations, adding that the university will not comment further during the appeal period.